实验任务一：
// 文件读写操作：格式化读、写文本文件 #include <stdio.h>#define N 80 #define M 100typedef struct {char name[N]; // 书名char author[N]; // 作者 } Book;void write(); void read();int main() {printf("测试1: 把图书信息写入文本文件\n");write();printf("\n测试2: 从文本文件读取图书信息, 打印输出到屏幕\n");read();return 0; }void write() {Book x[] = { {"《雕塑家》", "斯科特.麦克劳德"},{"《灯塔》", "克里斯多夫.夏布特"},{"《人的局限性》", "塞缪尔.约翰生"}, {"《永不停步：玛格丽特.阿特伍德传》", "罗斯玛丽.沙利文"},{"《大地之上》", "罗欣顿·米斯特里"}, {"《上学记》", "何兆武"}, {"《命运》", "蔡崇达"} };int n, i;FILE *fp;// 计算数组x中元素个数n = sizeof(x) / sizeof(x[0]); // 以写的方式打开文本文件data1.txt fp = fopen("data1.txt", "w");// 如果打开文件失败，输出提示信息并返回 if(fp == NULL) {printf("fail to open file to write\n");return;}// 将结构体数组x中的图书信息格式化写到fp指向的文件data1.txtfor(i = 0; i < n; ++i)fprintf(fp, "%-40s %-20s\n", x[i].name, x[i].author);fclose(fp); }void read() {Book x[M]; int i, n;FILE *fp;// 以读的方式打开文本文件data1.txt fp = fopen("data1.txt", "r");// 如果打开文件失败，输出提示信息并返回 if(fp == NULL) {printf("fail to open file to read\n");return;}// 从文件中读取图书信息，保存到结构体数组x中i = 0;while(fscanf(fp, "%s%s", x[i].name, x[i].author) != EOF) ++i;// 将图书信息打印输出到屏幕上n = i;for(i = 0; i < n; ++i)printf("%d. %-40s%-20s\n", i+1, x[i].name, x[i].author);fclose(fp); }
实验结果：
实验任务二：
// 文件读写操作：以数据块方式读、写二进制文件 #include <stdio.h>#define N 80 #define M 100typedef struct {char name[N]; // 书名char author[N]; // 作者 } Book;void write(); void read();int main() {printf("测试1: 把图书信息以数据块方式写入二进制文件\n");write();printf("\n测试2: 从二进制文件读取图书信息, 打印输出到屏幕\n");read();return 0; }void write() {Book x[] = { {"《雕塑家》", "斯科特.麦克劳德"},{"《灯塔》", "克里斯多夫.夏布特"},{"《人的局限性》", "塞缪尔.约翰生"}, {"《永不停步：玛格丽特.阿特伍德传》", "罗斯玛丽.沙利文"},{"《大地之上》", "罗欣顿·米斯特里"}, {"《上学记》", "何兆武"}, {"《命运》", "蔡崇达"} };int n, i;FILE *fp;// 计算数组x中元素个数n = sizeof(x) / sizeof(x[0]); // 以写的方式打开二进制文件data2.datfp = fopen("data2.dat", "wb");// 如果打开文件失败，输出提示信息并返回 if(fp == NULL) {printf("fail to open file to write\n");return;}// 将结构体数组x中的图书信息以数据块方式写入二进制文件data2.datfwrite(x, sizeof(Book), n, fp);fclose(fp); }void read() {Book x[M]; int i, n;FILE *fp;// 以读的方式打开二进制文件data2.datfp = fopen("data2.dat", "rb");// 如果打开文件失败，输出提示信息并返回 if(fp == NULL) {printf("fail to open file to read\n");return;}// 从二进制文件data2.dat以数据块方式读取图书信息存储到结构体数组xi = 0;while(fread(&x[i], sizeof(Book), 1, fp) == 1) ++i;// 在屏幕上打印输出n = i;for(i = 0; i < n; ++i)printf("%d. %-40s%-20s\n", i+1, x[i].name, x[i].author);fclose(fp); }
结果：
实验任务三：
// 文件读写操作：以字符、字符串形式读、写 #include <stdio.h> #define N 100 #define M 80void write(); void read_str(); void read_char();int main() {printf("测试1: 把一组字符信息以字符串方式写入文本文件\n");write();printf("\n测试2: 从文件以字符串方式读取, 输出到屏幕\n");read_str();printf("\n测试3: 从文件以单个字符方式读取, 输出到屏幕\n");read_char();return 0; }void write() {char *ptr[] = { "Working\'s Blues","Everything Will Flow","Streets of London","Perfect Day","Philadelphia"};int i, n;FILE *fp;fp = fopen("data3.txt", "w");if(fp == NULL) {printf("fail to open file to write\n");return;}n = sizeof(ptr)/sizeof(ptr[0]);for(i = 0; i < n; ++i) {fputs(ptr[i], fp);fputs("\n", fp);}fclose(fp); }void read_str() {char songs[N][M];int i, n;FILE *fp;fp = fopen("data3.txt", "r");if(fp == NULL) {printf("fail to open file to read\n");return;}i = 0;while(i < N && (fgets(songs[i], M, fp) != NULL))++i;n = i;for(i = 0; i < n; ++i)printf("%d. %s", i+1, songs[i]);fclose(fp); }void read_char() {int ch;FILE *fp;fp = fopen("data3.txt", "r");if(fp == NULL) {printf("fail to open file to read\n");return;}while((ch = fgetc(fp)) != EOF)putchar(ch);fclose(fp); }
结果：
问题一：这里的\是转义字符，用于将‘转换为字符,而不是c的语法
问题二：i<N,防止songs数组行下标越界，避免数据溢出
实验任务四：
#include<stdio.h> int main(){FILE *fp;int count=0,row=0;fp = fopen("data4.txt", "r");
if(fp==NULL){
printf("fail to open file");
return;
}
int ch;while((ch=fgetc(fp))!=EOF){if(ch=='\n'){row++;}if(ch!=' '&&ch!='\n'){count++;}}if(row>0||count>0){row++;}printf("data4.txt统计结果:\n行数:%d\n字符数(不计空白符):%d\n", row, count);return 0; }
结果：
实验任务五：
#include <stdio.h> #include <string.h>#define N 10typedef struct {long id; // 准考证号char name[20]; // 姓名float objective; // 客观题得分float subjective; // 操作题得分float sum; // 总分char result[10]; // 考试结果 } STU;// 函数声明 void read(STU st[], int n); void write(STU st[], int n); void output(STU st[], int n); int process(STU st[], int n, STU st_pass[]);int main() {STU stu[N], stu_pass[N];int cnt;double pass_rate;printf("从文件读入%d个考生信息...\n", N);read(stu, N);printf("\n对考生成绩进行统计...\n");cnt = process(stu, N, stu_pass);printf("\n通过考试的名单:\n");output(stu, N); // 输出所有考生完整信息到屏幕write(stu, N); // 输出考试通过的考生信息到文件 pass_rate = 1.0 * cnt / N;printf("\n本次等级考试通过率: %.2f%%\n", pass_rate * 100);return 0; }// 把所有考生完整信息输出到屏幕上 // 准考证号，姓名，客观题得分，操作题得分，总分，结果 void output(STU st[], int n) {int i;printf("准考证号\t姓名\t客观题得分\t操作题得分\t总分\t\t结果\n");for (i = 0; i < n; i++)printf("%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", st[i].id, st[i].name, st[i].objective, st[i].subjective, st[i].sum, st[i].result); }// 从文本文件examinee.txt读入考生信息:准考证号，姓名，客观题得分，操作题得分 void read(STU st[], int n) {int i;FILE *fin;fin = fopen("examinee.txt", "r");if (!fin){printf("fail to open file\n");return;}for (i = 0; i < n; i++)fscanf(fin, "%ld %s %f %f", &st[i].id, st[i].name, &st[i].objective, &st[i].subjective);fclose(fin); }// 把通过考试的考生完整信息写入文件list_pass.txt // 准考证号，姓名，客观题得分，操作题得分，总分，结果 void write(STU s[], int n) {FILE *fp;fp = fopen("list_pass.txt", "w");if (fp == NULL){printf("fail to open file to write");return;}fprintf(fp, "准考证号\t\t姓名\t\t客观题得分\t操作题得分\t\t总分\t\t结果\n");for (int i = 0; i < n; i++){fprintf(fp, "%ld\t%20s\t\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].result);}fclose(fp); }// 对考生信息进行处理：计算每位考生考试总分、结果；统计考试通过的人数 int process(STU st[], int n, STU st_pass[]) {int pass_count = 0;for (int i = 0; i < n; i++){st[i].sum = st[i].objective + st[i].subjective;if (st[i].sum >= 60){strcpy(st[i].result, "通过");st_pass[pass_count++] = st[i];}else{strcpy(st[i].result, "不及格");}}return pass_count; }
结果：
实验任务六：
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h>typedef struct {char id[20];char name[20];char major[30]; } Student;void swap(Student *a, Student *b) {Student temp = *a;*a = *b;*b = temp; }void sort_by_id(Student arr[], int n) {for (int i = 0; i < n - 1; i++){for (int j = 0; j < n - i - 1; j++){if (strcmp(arr[j].id, arr[j + 1].id) > 0){swap(&arr[j], &arr[j + 1]);}}} }int main() {FILE *fp;fp = fopen("list.txt", "r");if (fp == NULL){printf("Cannot open file!\n");return 1;}Student allStu[100];int total = 0;while (fscanf(fp, "%s %s %s", allStu[total].id, allStu[total].name, allStu[total].major) != EOF){total++;}fclose(fp);srand((unsigned)time(NULL));int flag[100] = {0};Student selected[5];int count = 0;while (count < 5){int idx = rand() % total;if (flag[idx] == 0){selected[count] = allStu[idx];flag[idx] = 1;count++;}}sort_by_id(selected, 5);char file_name[20];time_t t = time(NULL);struct tm *tm = localtime(&t);sprintf(file_name, "%04d%02d%02d.txt", tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday);printf("----------------%04d%02d%02d中奖名单----------------\n", tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday);for (int i = 0; i < 5; i++){printf("%s %s %s\n", selected[i].id, selected[i].name, selected[i].major);}FILE *out = fopen(file_name, "w");if (out == NULL){printf("Cannot create file!\n");return 1;}for (int i = 0; i < 5; i++){fprintf(out, "%s %s %s\n", selected[i].id, selected[i].name, selected[i].major);}fclose(out);printf("文件保存成功！\n");return 0; }
结果：
